Our long-term goal is to develop and commercialize a replaceable transcatheter aortic valve (TAV), which is initially deployed with a covered base anchored within native diseased aortic valve without paravalvular leakage and a separate modular valve component inside the base. Years later, after transcatheter aortic valve replacement (TAVR) degenerates and fails, the modular valve component can be retrieved and replaced with another valve component via transcatheter approach with a temporary valve. Goal of Phase I SBIR is to develop two-component TAV with base and replaceable valve and demonstrate retrievability of valve after implantation and release within the base. To date, no TAV on the market or in development has demonstrated this key step of retrieval after TAVR deployment. Success of Phase I would lead to Phase II where we would demonstrate modular valve component replacement using a temporary valve for hemodynamic stability during deployment. TAVR revolutionized treatment of severe aortic stenosis (AS). Randomized clinical trials proved TAVR improved survival over medical therapy for inoperable patients, making TAVR the gold standard therapy. Transfemoral TAVR also showed equivalent or superior outcomes when compared to surgical aortic valve replacement for high-risk and now, intermediate-risk patients. Large randomized trials are currently underway for low-risk surgical patients, with small studies showing TAVR and SAVR equivalence. As TAVR expands to younger, less risky patients, durability becomes TAVR's Achilles heel. Alarmingly, new TAVR durability data presented at EuroPCR May, 2016 showed early TAVR degeneration within 5-8 years, with 50% degeneration at 8 years. As TAVR expands to surgical patients 50-70s years old, a clinical unmet need has emerged to develop TAVR devices with replaceability as an option. We hypothesize that expanding TAVR to younger low- risk surgical patients will require a replaceable TAV to overcome limited TAVR durability. Our innovative solution is to develop a replaceable TAVR using a 2 component modular system: a permanent hollow covered base, with a removable valve component that can be replaced. Current 3rd generation TAVR have the ability to retrieve and reposition the valve for precise positioning during the implantation, but once released, none of the current designs allow for removability and replacement. Our goal here is to demonstrate removability of TAVR valve component once fully released. We propose following 3 aims: 1) Test a two-component, TAVR prototype with fully retrievable/removable valve component and implant in vitro in pulse duplicator to assess hemodynamics, 2) Demonstrate TAVR valve component repositionability then full release from delivery system , 3) Demonstrate TAVR valve component retrievability and removability by the retrieval system after full release of the TAVR. Phase I SBIR is the first step towards offering younger, healthier patients a removable and replaceable TAV. Our Phase II goals will be developing delivery systems with embedded temporary valve for hemodynamic stability and filters to capture embolic debris during TAVR valve removal and reimplantation.